What does ac motor have to do with a carbon brush
Ac motor USES carbon brush: winding asynchronous motor, ac commutator motor and electric motor and so on.
Ac motor carbon brush: carbon brush can be used in dc motor or ac motor commutator or slip rings as export import current sliding contact, its conductive, thermal conductivity and good lubrication performance, and has certain mechanical strength and commutation spark instincts. Almost all electric motors use a carbon brush, which is an important component of an electric machine.
Electric tools use single phase alternating current series motor or alternating current and dc series motor.